Thanks for your response. I got frustrated trying to figure out why it wouldn't release so figured I'd try to determine why. The 'O' ring seemed so tight in the 'U' of the brake, I put in my lathe and scraped a few thousandths off the thicker side. While not proportional, I can 'bump' the valve and it will now expand and release. Since I didn,t know the brand, I took the old rings to a hydraulic shop and matched them the best I could-don't know if they used some odd ball size. I did,also, drown them in vaseline. I agree the nose wheel idea is not great. I had more in mind using it to run up the DF engine and release. Their too small for the mains. Bill S.